Adjustable chair



Jan. 1 9, 1943.

R. P. RA-LSTON ADJUS TABLE CHAIR,

F i led Jan. 25, 1940 2 .Shets-Sheet 1 Z6 a; mm z?- Jan. 19, 1943. R. P. RALSTON 2,308,714

ADJUSTABLE CHAIR Filed Jan. 23, 1940 2 Sheets-Sheet 2 Patented Jan. 19, 1943 UNITED STATES PATENT OFFICE.

ADJUSTABLE CHAIR Robert P. Ralston, New Concord, Ohio Application January 23, 1940, Serial No. 315,209

7 Claims.

This invention is directed to an improvement in adjustable chairs which, while designed more particularly for beauty parlors and the like, are nevertheless intended for use wherever an adjustable chair may be required.

The primary object of the present invention is the provision of an adjustable chair, the seat, back and arm-rests of which are capable of being elevated and lowered in a step-by-step movement through the manipulation of a single lever through a comparatively small range of movement, a portion of the lever per se being manually operable to control the direction of setting or movement of the chair.

The improved chair in the general structure includes a connected seat, back and arm-rests mounted for movement vertically in both directions relative to a base frame; the movement of the chair being controlled by pawls cooperating with racks, with means governed by the handle lever or the adjustment of a portion of the handle lever for controlling the positions of the pawls in order that the operation of the handle lever for raising and lowering the chair may cause proper cooperative relation between the pawls and racks, whereby the parts to be elevated or lowered are moved in either direction in a step-by-step movement commensurate with the spacing of the rack teeth.

The invention is illustrated in the accompanying drawings, in which:

Figure 1 is a perspective view of the improved chair.

Figure 2 is a perspective view of the operating parts with the seat, back and arm-rests omitted.

Figure 3 is a view in side elevation showing the pawls and cooperating racks at one end of the elevating mechanism, with the pawl controlling means set for lowering the chair and the parts shown in position to control one of the pawls.

Figure 4 is a similar view showing the parts set in position to control the other of the pawls.

Figure 5 is a similar view with the pawl controlling mechanism set to permit elevation of the Parts.

Figure 6 is a plan view, partly in section, of Figure 5.

Figure 7 is a plan view, partly in section, showing the means for operating and controlling the positions of the pawls.

Figure 8 is an enlarged detail view showing the means for controlling the pawl controlling dog.

Figure 9 is a view in elevation, partly in section, of the operating handle lever, showing the means for controlling the pawl setting dog.

The improved chair comprises what is termed a main frame preferably though not necessarily of tubular material, having foot portions 2, upright portions 3 extending from the forward ends of the foot portions, side bars 4, and a rear bar 5, the inner ends of the foot portions being connected by a cross-bar 6.

Connected to and extending rearwardly from bar 6 are foot bars In. These bars at the rear extend upwardly as at H, and are connected at |2 to the side bars I of an auxiliary frame.

An auxiliary frame is provided, including side bars I, a rear cross bar 8, and a front bar- 9, the latter being connected at its ends to the upright portions 3 of the main frame; the side bars 7 being connected to the front bar 9.

The seat l3, back I4 hingedly connected by straps l5 to the seat, and arm-rests l6 supported on inverted U-shaped bars I8 connected to the seat are arranged as a unit, any conventional provision being made for holding the back at a desired angle to the seat.

It is to be understood in this connection that the particular form of the parts so far described, that is the frames and parts of the chair per se, are not particularly important and any construction is contemplated which will answer the purposes of the present invention, though as a general proposition the form illustrated in the particulars noted lends itself readily to agreeable and pleasing finish, rendering the chair attractive.

The seat proper and, of course, the back and arm-rests are supported on plate-likepillars I9 depending from brackets 20 secured to the bottom of the seat and arranged adjacent the side edges of the seat. These pillars are formed with longitudinally ranging slots 2 and are slidably mounted in guides 22 having inturned ends 23 to receive and guide the pillars. The guides 22 are of materially less length than the pillars and are secured to plates 24 fixed on the bars 1 of the auxiliary frame, as shown more particularly in Figure 2.- The guides 22 are formed with slots 25 to register with the slots 2| in the pillars. On the inner surface of each pillar at the vertical margins of the slots 2| are provided ribs 26, the outer edges of which are formed with teeth 21, the abrupt or holding margins 28 of which are at the lower portion of the teeth.

A hollow shaft 29 is rotatably mounted in th guides 22 below the slots 25 therein, such shaft passing through the slots 2| in the pillars 19. Fixed on the hollow shaft 29 immediately-adjacent each set of teeth 21 is a plate 30 extending in both directions beyond the shaft and in these plates are pawl-operating rods 3|, one on each side of the shaft 29, with the respective ends of each rod carrying a pawl 32 for cooperation with the teeth 21. Each set of pawls 32 at the respective ends of the mechanism is connected by a spring 33 tending to draw the free ends of the pawls together.

As the cooperation of the pawls and teeth serves to providefor both raising and lowering the seat and connected parts and as it is apparent that if the shaft 29 is rocked the spring 33 tending to draw the pawls into cooperation with the teeth will cause said pawls to engage successively in the teeth on the respective sides of the slots 2|, the rocking of the shaft 29 in one direction causing the pawl 32 on one side to engage and hold in a particular tooth while the opposite pawl is moving downwardly to engage in the next lower tooth. The obvious continuation of this operation will, of course, result in a gradual step-by-step elevation of the seat and connected parts.

However, if it is intended, through a similar manual operation of the shaft rocking means, to also lower the seat and connected parts in a step-by-step movement, means must be provided for holding the pawls successively out of cooperation with a particular tooth until the pawl moves below the next lower tooth and is then permitted to move inwardly to engage that tooth while the continued rocking of the shaft permits the parts to lower in the desired step-by-step movement.

To secure this result, a dog-operating rod 34 is mounted for sliding movement longitudinally of the hollow shaft 29. A dog 35 is pivotally mounted within the hollow shaft 29 and has a cam end 36 adapted to be projected through a slot 31 in the shaft 29. Obviously, when the rod 34 is moved toward the dog, the rounded end 38 of the rod will elevate the dog so that the cam portion 36 will project well above the surface of the shaft 29. On the withdrawal of the rod, the dog may be returned to normal position, that is at least level with the surface of the rod 29, either by gravity or, if preferred, by positive means, such as a spring 39. The dog 35 is arranged adjacent one set of pawls only, preferably that set remote from the handle lever to be later described.

A spring finger 40 is rigidly connected to each rod 3|, a sleeve 3| encircling the rod, with a pin passing through the finger 40, sleeve 3| and rod 3|, the free ends of the fingers overlying the path of movement of the dog 35, as clearly shown in Figures 3, 4 and of the drawings. When the dog-operating rod 34 is moved inwardly and the dog elevated, the rocking of the shaft 29 in one direction will cause the finger 40 connected to the rod 3|, which is being moved downwardly by the rocking of the shaft 29, to be engaged and elevated by the dog 35, as shown more particularly in Figure 3. This elevation of the particular finger 40 swings the rod 3| to which that finger is connected, so as to move the pawl 32 at each end ofthe rod 3| against the tension of the spring 33 to a position where the operative end of the pawl is free of the path of movement of the teeth with which it cooperates.

Under these circumstances, the rocking of the handle lever to be later described will permit the opposing pawl, that is the one held in cooperation with the teeth, to move downwardly, the opposing pawl of the pair being out of the plane of the teeth and permitting such movement of the pillar as will lower the parts. In this movement, of course, the dog moves into cooperation with the finger of the other pawl, but at this time the pawl 32, which has been previously held out of the plane of movement of the teeth, has passed the engaging portion of the next uppermost tooth and is permitted to ride into engagement with the tooth above the one it has passed, This checks the downward movement to the distance of one tooth, for as the shaft 29 is rocked to lower the engaged tooth, the finger 40 of that tooth is engaged by the dog 35 and it is moved out of the plane of its cooperating teeth, as illustrated more particularly in Figure 4. This permits a step-by-step lowering of the seat and connected parts.

It is, of course, apparent that the provision of the dog and the spring fingers is only necessary at one end of the shaft 29, for whatever movement is imparted to the dogs at this end will correspondingly operate the dogs at the opposite ends of the rods 3| because the rods are rotatably supported and the dogs are fixed to the rods.

The operating means for the parts involves a handle lever and cooperating parts including a sleeve 4| slidable on the shaft 29 beyond one pillar IS. The sleeve 4| is connected to the dogoperating rod 34 by a pin 42 which passes through the rod and through a slot 43 in the shaft 29, so that the sleeve is capable of longitudinal movement independent of the shaft 29. A casting 44 is fixed to the sleeve 4| and includes a pinion 45 arranged to engage a rack 46 on the sleeve. The pinion is connected to a rod 41 which extends rotatably through a protective hollow section 48 connected to the casting 44. The rod 41 extends above the section 48 and is provided with a handle 49.

Obviously, as the handle is rocked, the shaft 29 is rocked and the pawls 32 successively engaging in the teeth 2! will result in a step-bystep elevation of the chair and supported parts. If it is desired to lower the chair, the handle end 49 of the handle lever is turned, causing the pinion 45 to move the sleeve 4| and thereby the dogoperating rod 34 to elevate the dog and thus provide for the successive automatic control of the pawls necessary for the lowering of the chair, as previously described.

It is, of course, to be understood that the improved chair is to be specifically constructed, aside from the details noted, in accordance with the particular uses and purposes of the chair. The present chair is designed particularly for use in beauty shops, thoughcbviously it may be useful for dentists, barber shops and similar places. The various parts are constructed of metalexcept for the cushion elements, and such metal may be finished in any desired manner, such, for example, as nickel or chrome plating.

Shields are provided, though not illustrated,

which may cover the moving parts of the pillars,

guides and pawls, such shields being merely an ornamental finish and without any important part in the present invention.

What is claimed to be new is:

1. An adjustable chair including a seat, a sup porting frame, pillars depending from the seat and provided withspaced toothed racks, a shaft mounted for rotation with respect to the main frame, opposingpawls connected with the shaft for cooperation with the respective racks on the pillars, a rod connectingthe similar pawls at each end of the shaft, means for moving the shaft to cause similar movements of the respective pawls at each end of the shaft, a spring connecting the pawls at each end of the shaft for compelling the pawls to normally cooperate with both adjacent racks, a rod movable lengthwise of the shaft, a dog movable with the red to a position beyond the surface of the shaft, and spring fingers carried by each pawl of one pair to be engaged by the dog in the movement of the shaft, the engagement of the dog and the spring finger carried by the pawl which is moving upward in the operation of the shaft serving to move that pawl beyond the path of the cooperating teeth of the rack to permit the pawl to pass the immediately overlying tooth, the subsequent movement of the shaft in the opposite direction relieving the pawl of the action of the dog and spring finger and permitting it to engage the next succeeding overlying tooth of the rack, whereby in the movement of the shaft the pawls may be utilized to raise the pillars and seat or permit said pillars and seat to move downwardly.

2. A construction as defined in claim 1, wherein the rods connecting the similar pawls compel similar movement of the connected pawls in the operation of the dog and spring fingers.

3. A construction as defined in claim 1, wherein guides are provided to slidably receive the pillars and an auxiliary frame provided to support the guides, the auxiliary frame being rigidly connected to the supporting frame.

4. A construction as defined in claim 1, wherein the means for operating the shaft and rod includes a sleeve slidable on the shaft, a casting carried by the end of the sleeve, means for connecting the sleeve to the rod, the shaft being formed to permit the movement of the connecting means without moving the shaft, a gear connection in the casting for reciprocating the rod,

a handle projection rigid with the casting and extending therefrom, and a member movable in said handle projection and extending beyond the same and operable at will to actuate the gearing to shift the rod.

5. An adjustable chair including a supporting frame, a seat adjustable in both directions relative to the frame, a shaft mounted in the frame, means for manually rocking the shaft, pawls arranged in pairs depending from each side of the seat, bars carried by the shaft and extending at right angles thereto, a pawl supported at each end of each bar for movement relative to the racks, a spring connecting the pawl to cause them to engage the teeth of the racks normally, means connecting the similar pawls for each pair of racks, and manually operable means to control the pawl movement relative to the shaft during the respective operations of the shaft, said means providing for engagement of similar pawls for the respective racks to engage the racks in that rocking movement of the shaft tending to tilt the arms to lift the engaged pawl, said means acting to move the similar pawls cooperating with the respective racks out of cooperation with those racks when the shaft is operated to move the arms to cause such pawls to be moved upwardly, whereby the remaining pawls in cooperation with the shaft are moved downwardly to permit a descending movement of the racks and thereby of the seat.

6. A construction as defined in claim 5 wherein the means includes a rod movable longitudinally of the shaft, and a cam controlled by the rod to govern the pawl position.

7. A construction as defined in claim 5 wherein said means includes fingers connected to the respective pawls, a cam underlying the fingers and a rod operative in the shaft for controlling the pawl.

ROBERT P. RALSTON. 

